Mircro-electro-mechanical (MEM) sensors such as gyroscopes, accelerometers, vibration sensors, and microphones must be mounted in close proximity to an application specific integrated circuit (ASIC) control chip to realize optimum instrument performance. The path length of sensitive electrical nodes is typically held to 0.25 inches or less to minimize parasitic capacitance and noise susceptibility. This requirement, combined with the need to measure rotation or acceleration along three orthogonal axes in micromechanical inertial sensor assemblies (MMISA) has constrained system architectures to those typified by the competent munition advanced technology demonstration (CMATD) system shown in FIG. 1.
The MMISA in FIG. 1 occupies approximately 8 in3 of the 16 in3 available volume of the device. In order to reduce this volume it has been proposed to place each instrument at an angle. For example, in CMATD systems, the three gyro and three accel instruments are mounted on separate circuit boards which are in turn mounted orthogonal to each other. A circuit backplane and flexible cabeling are used to interconnect these six instruments. In order to reduce this volume it has been proposed to place the three gyro instruments onto a single circuit board and the three accel instruments onto single circuit board, which allows for a substantial reduction in redundant component. The challenge is in mounting the three gyro and three accel sensor devices orthogonal to each other on a coplanar surface while maintaining the close proximity to their associated ASICs.